Conflicting Jar Files

[ajncyn]

If I have a jar file in the common/lib folder in Tomcat and in the same file in the lib folder of my application, which one takes priority?

 

[byam]

It will load from the yourApp/WEB-INF/lib folder first.

However, "for classes which are part of J2SE (which means it will attempt loading first with its parent classloader before loading from its current repositories, regardless of the current delegation setting). This includes classes from the SAX and DOM APIs, Xalan, Xerces, and any classes which package name starts with "javax.".

For the later case, it will load from
1. Shared
2. Common/endorsed,
3. Common/lib,
4. JAVE_HOME/lib,
finally yourApp/WEB-INF/lib

For detail:

http://jakarta.apache.org/tomcat/tomcat-4.1-doc/class-loader-howto.html

 

[sedj]

As an addition - this behaviour is correct for tomcat4/5 but with tomcat3, jar in the lib dir would overrride webapp jars ...